About the Cover

About the Cover
Saccharomyces cerevisiae meiotic chromosomes in which the future sites of crossovers can be visualized. The synaptonemal complex protein Zip1 (red) indicates the tightly paired homologs, and the Zip3 foci (green) are thought to mark future crossover sites. Analysis of crossover frequencies can be extended genomewide with this cytological tool (see ROCKMILL, VOELKEL-MEIMAN and ROEDER, pp. 1745–1754).